The intermittent nature of renewable energy sources can create a mismatch between supply and demand, posing a challenge in providing reliable and efficient power supply. Energy storage presents a promising solution to this challenge. This study evaluates the effect of thermal energy storage (TES) on the performance of a 50 MW concentrated solar power (CSP) plant situated in Kuwait’s Shagaya Renewable Energy Park (SREP). The analysis focused on the year 2020 due to high levels of Direct Normal Irradiance (DNI) and effective utilization of Thermal Energy Storage (TES) in optimizing energy yield. The findings indicate that TES enabled the CSP plant to increase its energy generation by 48%, resulting in 160 GWh of net energy in 2020. A comparative seasonal analysis was conducted for August and January, which differ significantly in the amount of solar radiation received. In August, 25 GWh was generated, including 10.8 GWh from TES, while in January, 9 GWh was produced, with 2.1 GWh from TES. The plant’s performance during three consecutive days of sandstorms in 2020 was examined, focusing on the influence of TES. The results showed that during periods of high wind speeds and fluctuations in DNI, stored energy in TES accounted for 41% of the energy produced, compensating for losses. Overall, TES enhances the flexibility of CSP systems, playing a critical role in maintaining power loads and enabling dispatchability during adverse weather conditions. The study shows that integrating TES with CSP plants enhances power quality for future solar thermal projects in Kuwait.